Carrier for double side polishing

ABSTRACT

In a carrier of the invention, a thick ring-shaped support frame is provided at an outer periphery of a carrier body in which a workpiece housing hole for holding a workpiece is opened. An outer periphery of the support frame is provided with a teeth portion for engaging with driving gears for driving the carrier. The support frame is made of a different member from the carrier body. The carrier body is removably attached to the support frame by screws. The carrier body is made of a material suitable for holding a wafer. The support frame is made of a material suitable for engaging with driving gears for moving the carrier.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a double side polishing carrier suitably used for polishing both sides of a semiconductor wafer as a raw material of a semiconductor device. Specifically, the invention relates to a double side polishing carrier suitably used in a single wafer type double side polisher.

Priority is claimed on Japanese Patent Application No. 2004-358247, filed Dec. 10, 2004, the content of which is incorporated herein by reference.

2. Description of the Related Art

A double side polisher having a planetary gear mechanism has frequently been used for double side polishing of semiconductor wafers. The planetary gear type double side polisher is a kind of batch processing apparatus in which both sides of a plurality of wafers are polished simultaneously. In this type of double side polisher, a plurality of carriers are arranged about the rotating center of upper and lower rotating surface plates. Each of the plurality of carriers has a sufficiently smaller diameter than the surface plates. While holding one or a plurality of wafers, the carrier rotates in an interstitial space between the upper and lower surface plates. Along with rotating, the carrier also revolves around the rotation center of the surface plates. By this epicyclic movement of carriers in the interstitial space between the surface plates, both sides of a wafer held in each carrier are polished.

Recently, the diameter of a semiconductor wafer to be subjected to double side polishing has increased rapidly. Wafers of 300 mm in diameter are already being produced, and production of still larger wafers is expected in the future. A multi-carrier type polisher using a plurality of carriers is not preferable for double side polishing of such a large sized wafer, since the large wafer size requires a large apparatus. In such a large apparatus, a reduction of maintenance performance cannot be avoided. For example, in such a large apparatus, maintaining precision, and general maintenance and inspection of the apparatus are difficult. In addition, in order to satisfy a requirement for a highly flat wafer surface, it is desirable that working conditions for manufacturing wafers are optimized for each single wafer. From such a point of view, a single wafer type polisher is considered as preferable for double side polishing of large sized wafers.

A single wafer type double side polisher is a single carrier type apparatus using a single carrier having a diameter larger than the diameter of upper and lower rotating surface plates. This is the most important characteristic structure of the single wafer type double side polisher. In this polisher, a wafer is held in a carrier having a larger diameter than the wafer. Both sides of the large sized wafer are polished by a circular movement of the carrier in an interstitial space between the upper and lower rotating surface plates. Compared to the multi-carrier type polisher which simultaneously polishes a plurality of wafers held in a plurality of carriers, downsizing and cost reduction can be expected in the single wafer type double side polisher.

Japanese Unexamined Patent Application, First Publication No. 2001-315057 discloses a single wafer type double side polisher. In this apparatus, a carrier holds a wafer in an eccentric position. The carrier is arranged concentrically with the upper and lower surface plates, and rotates around the center axis. By the concentric rotation of the carrier around the center axis of the rotating surface plates, the wafer held in the eccentric position of the carrier revolves around the center of the carrier in an interstitial space between the rotating surface plates. As a result, both sides of the wafer are polished.

Circumferential velocity of a portion of the rotating surface plate increases with distance from the center from zero velocity at the center towards a maximum velocity at the periphery of the rotating surface plate. Therefore, polishing rate by the surface plate also differs significantly between the center portion and peripheral portion of the surface plate.

As exemplified by the apparatus of Japanese Unexamined Patent Application, First Publication No. 2001-315057, the single wafer type double side polisher has a principal structure that uses the entire portion of the surface plates for polishing a single wafer. Therefore, unevenness of polishing caused by an inequality in circumferential velocity of the portion of the surface plate is not negligible. From this point of view, compared to the multi-carrier type double side polisher using a plurality of carriers simultaneously, for example, like the planetary gear type double side polisher, the single wafer type double side polisher is disadvantageous for retaining flatness of a wafer.

In the case of the multi-carrier type double side polisher using a plurality of carriers, the plurality of carriers placed in the interstitial space between the upper and lower surface plates are arranged near the outer periphery of the surface plates. Therefore, the difference of circumferential velocity between the outer portion and inner portion of the surface plate has little influence on the wafer polishing. As a result, along with the effects of revolution and rotation of the carriers, the wafers held in the carriers are evenly polished.

In the practical polishing process by a single wafer type double side polisher, the wafer itself rotates in the carrier. In addition to this effect, as a countermeasure, for example, by supplying more abrasive fluid to the center portion than to the outer portion of the plate, unevenness of the wafer surface is maintained below the value expected from the partial inequality in circumferential velocity of the plate. However, it is still difficult to eliminate the influence of an unequal circumferential velocity of the plate portions, and therefore, it is difficult to ensure a sufficient flatness of the wafer.

In order to avoid the above-described problem of the single wafer type double side polisher, it is effective to mobilize the carrier with complex movement in the interstitial space between the upper and lower surface plates. By this movement, each portion of the carrier moves along a complex locus, and the effect of circumferential velocity of the rotating surface plate applied to each portion of the wafer is equalized. Therefore, the flatness of the wafer is improved. Based on this consideration, the inventors preliminarily disclosed a method and apparatus for double side polishing in Japanese Patent Application No. 2004-127074 (First Publication No. 2005-205585). In this apparatus, a carrier movement includes a circular movement around an eccentric position remote from the center as well as rotation in the circumferential direction. Where necessary, rotating surface plates are moved in a direction perpendicular to their rotation axis.

However, in order to mobilize the carrier with such compound movement including radial movement relative to the surface plates, it is necessary to make the external diameter of the carrier sufficiently greater than the external diameter of the surface plate so that the carrier moving in the radial direction is not completely removed from the interstitial space between the surface plates. For example, to polish a wafer of 300 mm in diameter by a surface plate of 380 mm in diameter, it is necessary to use a carrier having a diameter greater than 500 mm. As a result, overhang of the carrier outside the surface plate is not negligible. The overhanging portion of the carrier is shown as a portion outside the rotating surface plate 50 in FIG. 2. Such an overhanging portion causes a problem as follows.

Compared to the increase in wafer size as a raw material for a semiconductor device, an increase in wafer thickness is restricted to a lower level. A normal thickness of a 300 mm wafer is 0.775 mm. A carrier used to finish the wafer so as to have such thickness generally has a thickness of about 0.75 mm. In order to retain mechanical strength in such a thin and large carrier, the carrier is made of a highly rigid material such as glass fiber-reinforced epoxy resin.

When such a thin but large sized carrier having a gear wheel shape is subjected to a compound movement in an interstitial space between the upper and lower surface plates, the overhanging portion of the carrier is deformed by an external force applied from the outer periphery of the carrier by driving gears. When the carrier is subjected to a running torque by driving gears, the carrier tends to escape towards the thickness direction. As a result, the carrier is subjected to a load in the thickness direction. When most of the portion of the carrier is supported by the upper and lower surface plates, the carrier is not deformed by the load in the thickness direction. However, when the carrier has a significantly larger size than the surface plates, only a central portion of the carrier is supported by the surface plates, and a large unsupported overhanging portion of the carrier is deformed by the load in the thickness direction. As a result, a failure of the carrier occurs frequently.

Furthermore, when the overhanging portion of the carrier is deformed in the thickness direction, the deformed carrier made of a highly rigid material applies a load on the surface plates. Such a load destabilizes the load applied from the surface plates to the wafer, and therefore, reduces the precision of polishing.

In addition, the carrier made of glass fiber-reinforced epoxy resin generates a fine fibrous powder along with the driving of the carrier by driving gears arranged around the outer periphery of the carrier. This fibrous powder also has an adverse effect on the polishing, for example, by cutting flaws on the wafer surface.

When a carrier is used repeatedly, an inner surface of an opening of the carrier is damaged due to friction with a wafer held in the opening. Therefore, the carrier needs to be replaced with a new one after the using several tens of times. However, the conventional type of carrier is relatively expensive, partially because of the necessity of cutting teeth around the carrier. Therefore, frequent changing of the carrier causes an unavoidable increase of running cost of the polisher.

An object of the present invention is to provide a double side polishing carrier (a carrier used for polishing of both sides of workpieces), which can be used for single carrier type double side polisher. By using this carrier, although the carrier has a large diameter and is moved with compound movement including a radial component, deformation of an overhanging portion of the carrier, failure of the carrier caused by the deformation, and reduction of precision in polishing can effectively be prevented.

SUMMARY OF THE INVENTION

A double side polishing carrier of the invention is used in a single carrier type double side polisher which moves the carrier with compound movement. The carrier holding a workpiece (for example a wafer) is inserted between upper and lower surface plates of the polisher. The compound movement of the carrier includes a first movement in the circumferential direction, and a second movement having a radial component. By this compound movement, the workpiece held in the carrier is polished. The carrier comprises a disk shape carrier body having at least one opening (workpiece housing hole) for holding the workpiece; and a ring-shaped support frame which is provided at the outer periphery of the carrier body to support the carrier body. The support frame is formed thicker than the carrier body and has teeth in its periphery to engage with driving gears.

Since the double side polishing carrier of the invention is used in the single carrier type and compound movement type double-side polisher, the carrier has a large overhanging portion outside the surface plate. However, in this carrier, at the periphery of the disk shaped carrier body having at least one workpiece housing hole for holding the workpiece, a thick support frame is provided to support the carrier body. Therefore, running torque applied by the driving gear is accepted by the thick support frame, and deformation of the carrier in the thickness direction is restricted. For example, for supporting a carrier body of not more than 1 mm in thickness, a support frame of 10 mm in thickness and 15 mm in radial width from an inner circumferential edge to an outer edge of a tooth (addendum circle) may be used.

The peripheral support frame may be formed in integrally with the inner carrier body, or may be formed of a different member independent of the inner carrier body. By constructing the support frame as an independent member, the support frame may be made of a material different from the carrier body. For example, if the support frame is made of a material generating no fibrous powder, for example nylon 66 or the like, an adverse effect on polishing caused by the fibrous powder can be avoided.

In addition, by forming the support frame as an independent member, the carrier body supported by the frame may be removable. In this case, it is possible to use the support frame for a long period by exchanging the carrier body. By using the thick support frame, wear depletion of the frame caused by engagement with the driving gears is reduced and the life-span of the frame is lengthened. By using the support frame for a long period and changing the carrier body only, the cost of the carrier is reduced. Since the carrier body itself does not have teeth, the carrier body may be provided at a lower cost than that of a conventional carrier.

A double side polishing carrier of the invention may have dimensions as follows.

Where a diameter of the rotating surface plate is D1, it is preferable that an external diameter D2 of a thin carrier body inserted between the surface plates is not smaller than 1.2×D1 and not larger than 1.8×D1. More preferably, D2 is not smaller than 1.3×D1 and not larger than 1.5×D1 (see FIG. 2). When the external diameter D2 of the carrier body is only slightly larger than the diameter D1 of the surface plate, the overhanging portion is limited to have small area. In such a case, deformation of the overhanging portion remains below an allowable level. It is of no advantage and impractical to have an external diameter D2 of the carrier body that is much larger than the diameter D1 of the surface plate. Even if such a carrier is realized, deformation of the carrier cannot be sufficiently inhibited.

Where a thickness of the carrier body is d1, a preferable thickness d2 of a support frame is, not smaller than 10×d1 and not larger than 30×d1. More preferably, d2 is not smaller than 15×d1 and not larger than 20×d1 (FIG. 1). When the thickness d2 of the support frame is only slightly larger than the thickness d1 of the carrier body, lack of strength of the carrier is not effectively reduced, and the effect of preventing the deformation of the carrier is insufficient. When the thickness of the support frame d2 is much larger than d1, an increase in weight and volume make it difficult to handle the carrier. The thickness d1 of the carrier body is determined based on the finished thickness of the workpiece. For example, a thickness of a carrier body used for polishing a silicon wafer is about 0.7 mm.

A width W of the support frame in the radial direction (including the width of tooth portion) is preferably not smaller than 0.05×D2 and not larger than 0.1×D2, where D2 is the external diameter of the carrier body. More preferably, W is not smaller than 0.07×D2 and not larger than 0.08×D2. With a support frame having too small a width W, it is impossible to improve sufficiently a deficient strength of the carrier as a whole, thus it is impossible to inhibit deformation of the carrier effectively. When the width W of a support frame is too large, increased weight and volume of the frame make it difficult to handle the carrier. In addition, when using such a large carrier, the single wafer type polisher cannot have the advantageous characteristics that a small apparatus has.

The upper level of the carrier body may be coincident with the upper level of the support frame. Alternatively, it may be lower than the upper level of the support frame. In the former constitution, abrasive fluid supplied to the surface of the carrier is smoothly drained to the periphery without being prevented by the support frame surrounding the carrier body. In the latter constitution, abrasive fluid supplied to the surface of the carrier remains on the surface of the carrier body, and a workpiece is polished within the fluid. That is, the latter constitution enables a submerged polishing of the workpiece.

In the single wafer type double side polisher described in Japanese Unexamined Patent Application, First Publication No. 2001-315057, a peripheral portion of the carrier is made to have a large thickness. The purpose of this constitution is to fix the relative position of the concentrically rotating carrier and the surface plate by providing the carrier with a recessed portion to which the surface plate is fitted. Based on this purpose, the thin portion of the carrier has the same external diameter as the diameter of the surface plate. Therefore, the thin portion of the carrier does not overhang outside the surface plate, and is not deformed. In addition, the peripheral portion of the carrier is only slightly thicker than the thin portion, since the purpose of the formation of the thick portion is not to support the carrier strength, but to provide a recessed portion to which the surface plate is fitted. Therefore, a usage, constitution, and effect of the thick portion of the carrier is significantly different from the support frame of the double side polishing carrier of the present invention.

The carrier of the present invention is particularly effective for the single wafer type polishing method, in which a single wafer is held in a single carrier. While, the carrier of the invention may also be applied to a multi-carrier type polishing method in which a plurality of wafers are held in a single carrier. In the latter case, the carrier body is provided with a plurality of workpiece housing holes for holding wafers.

The double side polishing carrier of the invention is a large sized carrier used in a single carrier type double side polisher by moving the carrier with a compound movement including a radial component. In this carrier, a thick ring-shaped support frame is provided at the outer periphery of the disk-shaped carrier body having workpiece housing hole for holding a workpiece. By this constitution, it is possible to inhibit deformation of a large overhanging portion of the carrier, and therefore, it is possible to avoid failure of the carrier and reduction of the polishing precision accompanying the deformation of the carrier. Accordingly, by using the carrier of the invention, both sides of large sized workpieces can be polished with high precision and low cost.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross section of a main portion of a double side polishing carrier in a first embodiment of the invention.

FIG. 2A is a plan view of a carrier body of the carrier in FIG. 1.

FIG. 2B is a cross section of the carrier body along the line b-b of FIG. 2A.

FIG. 3A is a plan view of a support frame of the carrier in FIG. 1.

FIG. 3B is a cross section of the support frame along the line b-b of FIG. 3A.

FIG. 4 is a plan view of a carrier body of the carrier in a second embodiment of the invention.

FIG. 5 is a plan view of a carrier body of the carrier in a third embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the invention are explained with reference to the drawings.

FIG. 1 is a partial cross section showing a constitution of a double side polishing carrier in a first embodiment of the invention. FIGS. 2A and 2B are respectively a plan view and a cross section of a carrier body of the carrier. FIGS. 3A and 3B are respectively a plan view and a cross section of a support frame of the carrier.

In this embodiment, the double side polishing carrier is provided with a disk-shaped carrier body 10, and a ring-shaped support frame 20 attached to the periphery of the carrier body for supporting the main body. The support frame 20 is independent from the carrier body 10, and thus removable, and is fixed to the carrier body through screws 40.

The double side polishing carrier of this embodiment may be used for polishing a wafer of 300 mm in diameter. A workpiece housing hole 11 is provided in the central portion of the carrier body 10 for holding a workpiece. The workpiece housing hole is perforated in a concentric position, or in a slightly eccentric position compared to the center of the carrier body. In the peripheral portion of the carrier body 10, a plurality of tapped holes 12 are provided with a predetermined interval in the circumferential direction of the carrier body for fixing the carrier body 10 to the support frame 20.

In an interstitial space between upper and lower surface plates 50, the carrier body 10 moves in a plane perpendicular to the central axis of the surface plates. Therefore, the carrier body is made to have a constant thickness throughout its entire portion, and the thickness is controlled to be slightly thinner than a finished thickness of a wafer. For example, for a wafer of 0.775 mm in finished thickness, a preferable thickness of the carrier body 10 is about 0.75 mm. By this thickness a predetermined load is loaded on both surfaces of the wafer until the end stage of polishing.

In order to provide sufficient mechanical strength (rigidity) to the carrier body 10, the carrier body 10 is made of material such as, for example, epoxy resin reinforced with glass fiber (GFRP). Alternatively, carbon fiber-reinforced plastic (CFRP), and metals such as SK steel may also be used as the material for the carrier body 10. The selected material needs to satisfy a requirement of having high strength as a thin member.

External diameter D2 of the carrier body 10 is determined depending on the momentum of the carrier placed between the upper and lower surface plate, especially on the momentum in the radial direction in a plane perpendicular to the center axis of the surface plates. For example, for a workpiece housing hole 11 of slightly larger than 300 mm in diameter, D2 is selected from the range of 480 to 490 mm. If the carrier has only a small momentum in the radial direction, the carrier body 10 may have a small external diameter D2. If the carrier has a large momentum in the radial direction, a large external diameter D2 is needed for the carrier body 10.

The support frame 20 is a ring attached to the outer periphery of the carrier body 10. The support frame 20 is designed to be sufficiently thicker than the carrier body 10. For example, for a carrier body of 0.75 mm in thickness, the support frame is designed to have a thickness of about 10 mm. Along with such a design of thickness d2, the self-strength of the support frame also depends on a radial width W of the frame. In order to provide sufficient self-strength to the support frame 20, the support frame is designed to have a width W of, for example, about 20 mm.

Throughout the entire circumference of the peripheral surface of the support frame 20, the support frame 20 is provided with a teeth portion 21 by which the support frame 20 engages with a plurality of driving gears 30. A back surface (lower surface during polishing ) of the support frame is provided with a ring-shaped recessed portion 22 to which the outer periphery of the carrier body is fitted. In a cross sectional view of a frame, the recessed portion has an L-like contour opened towards the inner side of the frame. By forming the ring-shaped recessed portion, the front side ( upper side during polishing ) of the support frame is provided with a ring-shaped protruding portion 23 by which the carrier body 10 is supported. On the ring-shaped protruding portion 23, a plurality of tapped holes 24, 24 are provided to be coincident with holes 12, 12 of the carrier body 10 for inserting the screws 40.

For a support frame 20 of 10 mm in thickness d2, a preferable depth of the ring-shaped recessed portion 22 is, for example, 4 mm. In this case, the thickness of the ring-shaped protruding portion 23 is 6 mm.

Since the support frame 20 has little limitation on its dimensions, it is easy to provide sufficient strength to the support frame 20. Therefore, the support frame 20 may be made of various materials including, for example, nylon 66 which has relatively high strength but is inexpensive. The support frame 20 made of nylon 66 generates no fibrous powder by engaging with the driving gears 30. Alternatively, resins such as polycarbonate or PVC, and metals such as stainless steel may also be used as a material of the support frame 20.

By fitting the outer periphery of the carrier body 10 to the ring-shaped recessed portion 22 of the support frame 20, and by fixing the carrier body 10 to the ring-shaped protruding portion 23 of the support frame by screws 40, a carrier for double side polishing is completed.

During the double side polishing process, a wafer is held in a workpiece housing hole 11 in the carrier body 10. At that state, the carrier body 10 is inserted between upper and lower surface plates 50 (see FIG. 2). The carrier is rotated in the circumferential direction by the driving gears 30 engaging with the teeth portion 21 of the support frame 20 from the outer periphery of the support frame 20. Simultaneously, by swinging synchronously a plurality of driving gears 30, the carrier is subjected to a circular movement around an eccentric position distant from the center of the carrier. By this driving, the carrier moves with compound movement including a first movement in the circumferential direction and a second movement having a radial component. Such a complex movement of the carrier enhances the flatness of the wafer.

The carrier is subjected to a rotation torque by the plurality of driving gears 30 arranged around the outer periphery of the carrier. Since the carrier has a larger diameter than the diameter of the surface plate, and is moved in the radial direction, the carrier exhibits a large overhanging portion. Although the carrier body 10 holding the wafer is thin, sufficient rigidity is given to the carrier body 10 supported by the thick support frame 20 arranged in the outer periphery of the carrier. Therefore, the overhanging portion of the carrier is substantially free from deformation in the thickness direction by the rotation torque applied by the driving gears 30.

Accordingly, failure of the carrier by its deformation can be prevented. The inventors confirmed that during the double side polishing of wafers of 300 mm in diameter, by using the carrier of the invention, the failure frequency of carriers is reduced to a value not more than 0.1% of the case in which carriers having a constant thickness were used. In addition, a load applied by the surface plate to the carrier is free from deviation caused by deformation of the carrier. Such a stabilized load enhances the precision in the polishing process.

In addition, since the double side polishing carrier of the embodiment is surrounded by the ring-shaped protruding portion 23 of the support frame 20, circular recess 14 is formed on the upper surface of the carrier body 10. Abrasive fluid supplied during the wafer polishing process remains in the recess 14, and as a result, the carrier can be applied to submerged wafer polishing.

By increasing the thickness of the teeth portion 21 through which the carrier is driven, a contact width of each tooth and the driving gear is enlarged. As a result, wear of the teeth portion 21 and the driving gear is inhibited and their life span is lengthened. In a thin carrier having thin teeth, the teeth portion 21 suffers extensive wear. In addition, driving gears 30 engaging with the teeth at small contact area also suffer remarkable wear.

When the inner surface of the workpiece housing hole 11 for holding the workpiece is damaged, the life of the carrier body 10 exceeds the working limit. At that time, the carrier body 10 is removed from the support frame 20, and replaced by the new one. Thus, the support frame 20 may be used repeatedly and the carrier can be used for a long time only by changing the carrier body 10. Since the carrier body 10 does not have teeth in its periphery, it is inexpensive compared with the conventional carrier. Therefore, by using the carrier of the invention, it is possible to reduce the cost of changing the carrier compared to the case using conventional carriers.

FIG.4 is a plan view of a carrier body 10 used in a second embodiment of the invention. The difference between this carrier body l and the above-described carrier body 10 of the first embodiment is that a plurality of holes 13, 13 are provided around the periphery of the workpiece housing hole 11. With these small holes 13, 13, drainage of abrasive fluid is enhanced. Even though the upper surface of the support frame 20 is placed at a higher level than the upper surface of the carrier body 10, by providing the holes 13, abrasive fluid may be effectively drained. By enhancing draining of the abrasive fluid, new abrasive fluid is continuously supplied to the carrier. Therefore, a workpiece is rapidly polished and the precision of the finished surface is enhanced.

A similar effect can be obtained by having the upper surface of the support frame 20 lower than the upper surface of the carrier body 10. By combination of this setting and the above described holes 13, draining of the abrasive fluid is further enhanced. While, in some cases of polishing, the above described submerged polishing is rather preferable.

FIG. 5 is a plan view of a carrier body 10 used in a third embodiment of the double side polishing carrier of the invention. Compared with the above-described carrier body 10, the carrier body 10 is different in that a plurality of workpiece housing holes 11 are provided to the carrier body 10. For example, to polish three wafers simultaneously, three workpiece housing holes 11, 11, and 11 each having a diameter slightly larger than the wafer diameter are arranged around the center at regular intervals. The diameter D1 of the surface plate is slightly larger than the diameter of the wafer. For example, for polishing wafers of 200 mm in diameter using the carrier of this embodiment, surface plates having a diameter D1 of 230 to 240 mm may preferably be used. The diameter D2 of the carrier body 10 and the size of the support frame 20 are the same as the other embodiment.

As described above, by removing the support frame 20 from the carrier body 10, the support frame 20 can be reused even when a different type of carrier is applied, and thus it is highly advantageous.

While preferred embodiments of the invention have been described and illustrated above, it should be understood that these are exemplary of the invention and are not to be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit or scope of the present invention. Accordingly, the invention is not to be considered as being limited by the foregoing description, and is only limited by the scope of the appended claims. 

1. A carrier for double side polishing which can be used in a single carrier type and compound movement type double side polisher in which the carrier holding a workpiece is held between upper and lower surface plates, and is moved with compound movement including a first movement in a circumferential direction and a second movement having a radial component, the carrier comprising: a disk-shaped carrier body having an outer periphery and at least one opening for holding the workpiece; and a ring-shape support frame provided at an outer periphery of the carrier body to support the carrier body, wherein the support frame is thicker than the carrier body, and comprises a teeth portion at its periphery for engaging with driving gears of the double side polisher for driving the carrier.
 2. A carrier for double side polishing according to claim 1, wherein the support frame which is provided to support the carrier body is made of a member independent of the carrier body, and is removable from the carrier body.
 3. A carrier for double side polishing according to claim 2, wherein the support frame which is provided to support the carrier body is made of a material having different properties from the carrier body.
 4. A carrier for double side polishing according to claim 1, wherein an upper surface of the support frame is placed at a position higher than an upper surface of the carrier body.
 5. A carrier for double side polishing according to claim 1, wherein an upper surface of the support frame is placed at a position lower than an upper surface of the carrier body.
 6. A method for polishing a semiconductor wafer utilizing a carrier for double side polishing according to claim
 1. 